The listcontplot function creates a 2-D contour plot of a grid (list of lists or Matrix) of numeric values.

If the optional ranges r1 and r2 are supplied then the x-values and y-values are assumed to correspond to those of a uniform grid over the region defined by ranges r1 and r2, and $\mathrm{zij}$ is the function value at grid point $\left(i\,j\right)$. If r1 or r2 is not provided, then the ranges are taken as the positive integers up to the dimensions of the data.

Remaining arguments are interpreted as plot options. See plot/options for a list of possible options.

Option levels is provided as a synonym of the option contours. Either of these specifies the number of contours to draw, the default being eight.

The filledregions=true option can be specified to obtain a filled contour plot. The coloring option can, in this case, be used to specify a gradation in color, or color range. The default is a color range from red to yellow. To specify a color range, use the form coloring=[a,b], where a and b refer to colors recognized by plot. See plot[color] for an explanation of colors.

Data saved in external files may be imported into a Matrix with the ImportMatrix command and passed to listcontplot.

Note that the plot grid does not correspond exactly in orientation with the display of the list or Matrix data as it is printed in Maple. Instead, the $i$-th sublist or row of the Matrix corresponds to data values with x-coordinate equal to $i$.

$\mathrm{with}\left(\mathrm{plots}\right)\:$

$\mathrm{listcontplot}\left(\left[\mathrm{seq}\left(\left[\mathrm{seq}\left(\sin \left(\frac{\frac{x}{5}y}{5}\right)\,x=-15..15\right)\right]\,y=-15..15\right)\right]\right)$

$\mathrm{listcontplot}\left(\mathrm{Matrix}\left(\left[\mathrm{seq}\left(\left[\mathrm{seq}\left(\sin \left(\frac{\left(i-15\right)\left(j-10\right)}{20\mathrm{\pi }}\right)\,i=1..30\right)\right]\,j=1..20\right)\right]\right)\right)$

$\mathrm{listcontplot}\left(\left[\mathrm{seq}\left(\left[\mathrm{seq}\left(\sin \left(\frac{\left(i-15\right)\left(j-10\right)}{20\mathrm{\pi }}\right)\,i=1..30\right)\right]\,j=1..20\right)\right]\,\mathrm{filledregions}=\mathrm{true}\right)$

The G parameter was updated in Maple 15.

The plots[listcontplot] command was updated in Maple 2025.

The r1 and r2 option was introduced in Maple 2025.

For more information on Maple 2025 changes, see Updates in Maple 2025.